They step, sway, slide and spin to the booming beat.
"If you're sexy and you know it clap your hands,'' the song demands, and the dancers clap in unison.
This isn't Saturday night in Ybor City. It's Monday morning at the Progress Village Senior Nutrition Center, where a dozen or so women in their sixties and beyond follow the moves of longtime Zumba instructor Michelle Watkins, who leads with grace and vigor — and an oxygen generator strapped to her back.
"I love it,'' said Watkins, 64, who has a disease that scarred her lungs and restricted her breathing. "As long as I have my girlfriend with me''— her oxygen pack — "I'm good.''
Watkins is one of hundreds volunteering their time in a variety of ways to Hillsborough County Aging Services department. She recently was featured on the county's web site, hillsboroughcounty.org.
She had taught dance at recreation centers in Washington, D.C., and senior centers in Atlanta and wanted to continue when she moved to Hillsborough County in 2012. She applied to volunteer at senior centers, teaching Zumba Gold, which offers older fitness buffs a less frenzied pace than traditional Zumba. The music pounds out Caribbean, salsa and rhythm and blues three mornings a week for Watkin's dancers, as Watkins shouts commands, like "kick'' or "sway'' or "move those arms!'' The other seniors play cards, chat or watch the show and sometimes cheer.
Word has spread in the five years since she started, drawing people from outside Progress Village. They wear purple and lime green T-shirts with "P.V. Senior Fitness'' on the front and "Keep It Movin' '' on the back.
"I wanted something to get us motivated,'' Watkins said. "It's all about moving; you've got to keep moving, keep moving. So that's our motto – keep it movin'.''
Rosa Carr, 72, heard about the Zumba Gold class and soon found herself dancing in the morning. When she retired as a medical technician, she said, she just sat around for a year. "I said, I've got to get out and do something. I need to move.''
She's tired after the 50-minute workouts, "but it's a good tired.'' And she's always up for the next class. "I'm lost if I don't come here.''
For Deborah Knight, 62, the classes help ease the pain of fibromyalgia.
"I'm here because I'm around people; it gives me more encouragement to keep it moving,'' she said. "I really cannot exercise alone. I can't afford to fall.''
She has come to view the group as a family, echoing a common sentiment.
In this family, Watkins is the matriarch.
"She does her thing out there, so she is a lot of inspiration,'' said Knight. "Some people, like Michelle, just keep it moving, keep it going, don't let it bother them. Some of them just sit back and (say), 'Woe is me.' ''
It was 2014 when Watkins was diagnosed with sarcoidosis, characterized by inflammatory growths that damaged her lungs by leaving scar tissue.
When she first went on supplementary oxygen, she rolled a tank around behind her, which really got in the way when she led her exercise class. "I'm going to trip everybody up,'' she thought. The problem was solved when she got the portable oxygen generator that she wears like a backpack.
The idea of the senior centers is "to keep active seniors active,'' said Terence Steward, director of the Progress Village center, and Watkins makes sure that happens.
She helps create the atmosphere he's looking for at the center, "when people wake up in the morning and say, 'Man, can't wait to get to the center!'''
Contact Philip Morgan at firstname.lastname@example.org.